Various kinds of folding knifes are available in the market. Referring to FIGS. 1 and 2 for one of the traditional folding knifes, the folding knife 1 is consisted of a handle 100 and a blade 110, wherein an end of the blade 110 is pivotally coupled into an end of the handle 100 by a first pivot 120, and the handle 100 further includes a latch element 130 and a resilient element 140 therein. The latch element 130 is pivotally coupled into the handle 100 by a second pivot 131, and an end of the latch element 130 is pressed onto an end of the blade 110, and another end of the latch element 130 is extended towards another end of the handle 100, and another end of the latch element 130 has a pressing portion 150 which can be turned out from the handle 100. An end of the resilient element 140 is fixed into the handle 100 and disposed at a position away from the first pivot 120, and another end of the resilient element 140 is pressed onto another end of the latch element 130, such that the resilient element 140 can push the latch element 130 to latch and fix the blade 110 at a status of being extended out of the handle 100 or latch and fix the blade 110 at a status of being stored into the handle 100. If a user controls the blade 110 such that the blade 110 can be movably extended out of or stored into the handle 100, the latch element 130 will be pushed towards the resilient element 140 by the pressing portion 150 to release the blade 110 from the latch of the latch element 130.
To prevent the pressing portion 150 from being collided or compressed accidentally or the user from releasing the latch of the latch element 130 with the blade 110 by mistake and thus the blade 110 may have the risk of being turned out, it is necessary to design the folding knife 1 in such a way that when a user wants to turn the blade 110 out of the handle 100, the user needs to hold the handle 100 by one hand and presses the pressing portion 150 to release the latch of the latch element 130 with the blade 110, while the blade 110 is being pulled by another hand in order to turn the blade 110 out from the handle 100. In other words, when the user presses the pressing portion 150 to release the latch of the latch element 130 with the blade 110, the user has to turn the blade 110 out from the handle 100 by both hands.
However, such good intention causes another risk, since the folding knife 1 cannot be used immediately by one hand during a special or emergency situation. For instance, if a diver's hand is tangled by a fish net while the diver is diving, the diver will not be able to use the folding knife 1 to cut the fish net immediately by the other hand, and thus causing a fatal threat to the diver.
Further, when the user returns the blade 110 from the outside of the handle 100 into the handle 100, the user needs to hold the handle 100 by a palm and press the pressing portion 150 to release the latch of the latch element 130 with the blade 110 while pushing the blade 110 by another hand in order to turn the blade 110 into the handle 100. However, the user's palm is still holding the handle 110 at the moment when the blade 110 is being turned into the handle 100. When the user turns the blade 110 towards the handle 100 at a position on the moving route into the handle, the user may cut his or her palm that is still holding handle 100 accidentally and thus causing a serious injury to the user.
In summation, finding a way of designing a novel folding knife to overcome the shortcomings of the traditional folding knifes and enhancing the safety and convenience of the knife becomes an important subject for manufacturers.